When installing a pitched roof on a commercial or residential structure, it is generally recommended that the roof extend beyond the fascia board to allow water to drain into a gutter system. Failure to provide an adequate extension of the roof may cause water to run behind the gutter system, leading to damage of the fascia board and other components of the structure. The conventional technique for extending the roof to the recommended distance is to install a plastic or sheet-metal strip referred to as a “drip edge” at the edge of the roof. This strip attaches directly to the roof and directs water down into the gutter system.
Even with a properly installed drip edge, water may still penetrate the space between the roof and the roof deck. For example, “ice dams” may build up on the gutters and eaves of roofs during freeze-melt cycles and result in trapped water that could penetrate the deck. Additionally, wind may drive water up the slope of a roof, forcing the water under the shingles. To address these issues, a waterproofing shingle underlayment may be installed directly on the roof deck surface. The waterproofing shingle underlayment provides a protective barrier, preventing moisture from contacting the underlying roof deck.
In conventional roofing applications, the drip edge is a device which is separate from the waterproofing shingle underlayment. This results in various cost and time inefficiencies, as the two products must be purchased and installed separately. Additionally, as separate products, there is a risk that the drip edge and the waterproofing shingle underlayment will not be collectively installed in a correct manner, thus reducing their overall effectiveness in moisture prevention. Accordingly, it is desired to create an integrated system which includes both a waterproofing shingle underlayment and a drip edge in a single product.